#1Lib1Ref, the annual campaign where librarians add references to improve Wikipedia, is coming back again this year, running from May 15th to June 5th, 2018.

Why twice? We heard from you a desire to run it again out of excitement, because May is not summer vacation for the southern hemisphere, and because Spanish Wikipedia's birthday also falls in May. This is a great expansion of the event and it means that there is another opportunity to make Wikipedia more factual and verifiable by leveraging the expertise of librarians around the world.

How does this relate to the main campaign in January? We encourage librarians, community members, and affiliates to make 1Lib1Ref their own. So whether we call this 1Lib1Ref May, 1Lib1Ref for the Southern Hemisphere, or 1Lib1Ref Strikes Back, the point is the excitement is building again, and we'd like you to be a part of it.

If I participated in January, do I have to do it again in May? It's entirely up to you, this is just another chance if you want to do more, or if you couldn't get around to January activities. This is a pilot for us, too, so we'll see how it goes and discuss what we learned after the May campaign.

How can you get involved?

See updated dates and details on this page. The rest of the process is the same.

Imagine a World where Every Librarian Added One More Reference to Wikipedia.

Wikipedia is a first stop for researchers. Let's make it better! Your goal today is to add one reference to Wikipedia! Any citation to a reliable source is a benefit to Wikipedia readers worldwide. When you add the reference to the article, make sure to include the hashtag #1Lib1Ref in the edit summary so that we can track participation.

Why Should I Participate?

Wikipedia is an invaluable part of every researcher's process. More references make Wikipedia a better reference tool. Join us, and make a small contribution to the sum of all human knowledge!

Because anyone can edit Wikipedia, the Wikipedia community has developed a core strategy to ensure the quality of information in its articles: including footnotes to reliable sources to allow Wikipedia readers to "verify" the information. This strategy helps the global volunteer community effectively work towards meeting Wikipedia's vision: creating "the sum of all human knowledge."

Readers and editors who don't feel confident about a piece of information in an article can add a "citation needed" tag next to that statement. These tags are similar to reference questions: members of the public asking for reliable research to back up the information they are reading. English Wikipedia alone has over 380,000 citation needed statements.